LECTURE 13 - SOLUBLE FACTORS AND INTERMEDIATES OF OXIDATIVE PHOSPHORYLATION

Abstract

This chapter focuses on soluble factors and intermediates of oxidative phosphorylation. The first submitochondrial system that catalyzed oxidative phosphorylation was obtained from Escherichia coli. The chapter discusses the soluble factors in oxidative phosphorylation, namely, nonprotein factors and protein coupling factors. Ribonucleic acid was reported to act as a ligand between a soluble coupling factor and oxidizing particles obtained from Alcaligenes faecalis. The first suggestion that quinones participate in oxidative phosphorylation came from studies of liver mitochondria of animals that were fed a diet deficient in vitamin K. The resolution of protein factors from the multienzyme system of oxidative phosphorylation in mitochondria has been progressing very slowly despite extensive efforts in several laboratories. The coupling factor 1 (F1) was purified from beef-heart mitochondria and was shown to catalyze the hydrolysis of ATP. The chapter presents the relationship between F1 and the P32i–ATP exchange reaction.